 
 ;;----------------------------------------
 
-(def blue-whales (do-filter "type='blue whale'" whales '(:type) #(= "blue whale" %)))
-(insert *metamodel* blue-whales)
+(let [half-max-length (/ max-length 2)]
+  (def longer-whales (do-filter "longer" whales '(:length) #(> % half-max-length))))
+
+(insert *metamodel* longer-whales)
+
+(let [half-max-weight (/ max-weight 2)]
+  (def heavier-whales (do-filter "heavier" whales '(:weight) #(> % half-max-weight))))
+
+(insert *metamodel* heavier-whales)
 
 ;;----------------------------------------
 ;; demonstrate transformation - only selecting a subset of the

;; attributes...
;;----------------------------------------

(def blue-whales-weight (do-transform "weight" blue-whales :time :version :weight))
(insert *metamodel* blue-whales-weight)

(def blue-whales-length (do-transform "length" blue-whales :time :version :length))
(insert *metamodel* blue-whales-length)

;;----------------------------------------
;; try a transformation on top of a filtration

	    "beaked whale"
	    ])

(def max-weight 172) ;; metric tons
(def max-length 32.9) ;; metres

(defn rnd [seq] (nth seq (rand-int (count seq))))

;; IDEAS
